package com.fabolab.jetset.core.security;


	/**
	 * Encode an MD5 digest into a String.
	 * <p>
	 * The 128 bit MD5 hash is converted into a 32 character long String.
	 * Each character of the String is the hexadecimal representation of 4 bits
	 * of the digest.
	 *
	 * @author Remy Maucherat
	 * @version $Id: MD5Encoder.java 939305 2010-04-29 13:43:39Z kkolinko $
	 */
public final class MD5Encoder {


		private static final char[] hexadecimal =
	    {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
	     'a', 'b', 'c', 'd', 'e', 'f'};


	    /**
	     * Encodes the 128 bit (16 bytes) MD5 into a 32 character String.
	     *
	     * @param binaryData Array containing the digest
	     * @return Encoded MD5, or null if encoding failed
	     */
	    public String encode( byte[] binaryData ) {

	        if (binaryData.length != 16)
	            return null;

	        char[] buffer = new char[32];

	        for (int i=0; i<16; i++) {
	            int low = binaryData[i] & 0x0f;
	            int high = (binaryData[i] & 0xf0) >> 4;
	            buffer[i*2] = hexadecimal[high];
	            buffer[i*2 + 1] = hexadecimal[low];
	        }

	        return new String(buffer);

	    }


	}